Fat-soluble drugs

Unchanged passive diffusion and no change in bioavailability for most drugs l Active transport and i bioavailability for some drugs l First-pass extraction and T bioavailability for some drugs i Volume of distribution and T plasma concentration of water-soluble drugs T Volume of distribution and T terminal disposition half-life (t ) for fat-soluble drugs... 

Higher concentration of drugs that distribute in body fluids increased distribution and often prolonged elimination half-life of fat-soluble drugs... 

In older persons, the relative increase in body fat and the decrease in lean body mass alter drug distribution so that fat-soluble drugs are distributed more widely and water-soluble drugs are distributed less widely... 

Decreased serum albumin elimination half-lives of fat-soluble drugs... 

The effects of fat-soluble drugs may be increased in cachectic patients. 

Cholestasis may decrease the absorption of fat-soluble drugs such as norgestimate and gestodene. 

Distribution 1 Volume of distribution and concentration of water soluble drugs t Volume of distribution and half-life for fat soluble drugs t or X free fraction of highly plasma protein-bound drugs 1 Clearance and half-life for some Phase I... 

Canine Greyhound Decreased body fat results in decreased volume of distribution of fat soluble drugs such as anesthetics and thiobarbiturates. Lower cytochrome P450 (CYP2bll) levels and hydroxylase activity decreases rate of metabolism for some compounds, leading to longer Tl/2. [3,4] [5,6]... 

Only a small amount of drug can be absorbed in any one administration For a fat-soluble drug, absorption is rapid and effective Can cause damage when the drug is irritating or disrupts blood flow May be used for many drugs in pill form... 

In general, fat-soluble drugs tend to get locked away in fat depots and consequently do not reach the target protein very efficiently. 

This is the State tree of South Carolina, being the only palm indigenous to the east coast of North America. Its seeds (which are used to derive the pharmaceutical) are rich in fatty acids, their esters, and sterols. The extract of these seeds is recommended for mild symptoms referable to the prostate, without pharmacological rationale, and with the danger that patients will use the product to temporize for symptoms that could lead to the early diagnosis of malignancy. The doses administered are usually insufficient to reduce the absorption of oral fat-soluble drugs, but it would seem wise to separate the administration of vitamin D, warfarin, etc. and this complementary therapy. 

The role of bile acids in the absorption of other lipids such as cholesterol, fat-soluble vitamins, and fat-soluble drugs is similar to that described for fat (2). Bile acids are considered to influence the rate of hydrolysis of ingested cholesterol esters by interacting with cholesterol esterase and protecting it from tryptic digestion (86). Bile acids also influence the cleavage rate of / -carotene (87) conceivably, this effect is mediated on the surface of the cell. 

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